1. Field of the Invention
The present invention relates to a method and a system for distributing TV content over a network, especially an IP network, wherein the TV content is comprising a main content and an advertisement content and wherein a multicast address on which a TV channel for the main content is distributed within the network is transmitted to an user as a connectivity information.
2. Description Of The Related Art
Distribution of TV (Television) content over for example IP (Internet Protocol) networks usually involves IP multicasting in order to save bandwidth consumption compared to IP unicasting. Before an IPTV set (e.g. IPTV Set Top Box) can “tune-in” into a TV channel on the IP network it first needs to learn the IP multicast address on which the TV channel is broadcasted or distributed in the operator's network.
The ultimate problem when trying to deliver targeted content in IP networks is the bandwidth consumption caused by unicast point-to-point traffic. Although this might be feasible for traditional internet usage such as web browsing and email it causes serious problems in IPTV systems. The key difference is that an IPTV system has partially hard realtime requirements to the network and requires a sufficient sustained bandwidth for the AV (Audio-Video) content delivery. In order to be able to deliver IPTV channels to large numbers of users IP multicasting must be used to keep the bandwidth consumption at an acceptable limit for the operator's core network. Multicasting IPTV content for broadcasting TV channels works fine because all the users that are watching the same IPTV channel are supposed to see the same content. However, this does not apply in targeted advertisement scenarios, where users that are watching the same IPTV channel are supposed to see different advertisement content or advertisement segments at the same time. Although switching from IP multicasting to IP unicasting during advertisement breaks would enable delivery of targeted advertisement content or advertisement segments to individual users, it would also exceed the IPTV networks bandwidth capacities.